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From Edson Carlos Ericksson Richter <edson.rich...@mgrinformatica.com.br>
Subject Re: Language based ordering is possible in Derby
Date Thu, 03 Nov 2005 15:06:43 GMT
See comments inline, please...

Daniel John Debrunner escreveu:

>Rick Hillegas wrote:
>>Dan's workaround is very useful and √ėyvind's suggestion is interesting
>>also. It's worth pointing out that the need for these workarounds should
>>decrease after we fix bug 533 (the re-enabling of the natonal character
>>datatypes). I hope to get to that bug in 10.2. The national character
>>datatypes will give us language-sensitive collation in indexes and sorts.
Thats sounds great! A must have for us, at latin american coutries...

>Exactly, this is a workaround to help users with 10.1.
>That's great you are looking at national character types for 10.2. Even
>with national characters this functionality is useful because it allows
>sort orders per statement, and on non-national character types. Though
>there are probably advantages to building the functionality into the engine.
Probably, the most important are that using large tables with "order by 
SOME_FUNCTION(some_col)" could not be optimized unless you could index 
as "create index IDX_SOMETHING on MY_TABLE (SOME_FUNCTION(some_col))" 
too... Could Derby create and use indexes based on functions computing?
I think using national character datatypes will give that kind of 
optimization, don't?

Best regards,

Edson Richter

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